Method for forming bezel pattern of display substrate

ABSTRACT

Provided is a method for forming a bezel pattern of a display panel, the method including: attaching a release film including a non-pattern portion to a panel; printing at least one bezel pattern by applying an ink composition on the panel; and removing the release film from the panel.

This application is a 35 USC §371 National Stage entry of InternationalApplication No. PCT/KR2013/006007, filed on Jul. 5, 2013, which claimspriority from Korean Patent Application No. 10-2012-0075670, filed onJul. 11, 2012, in the Korean Intellectual Property Office, all of whichare incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present application relates to a method for forming a bezel patternof a display panel, a release film used in the method for forming abezel pattern of a display panel, a display panel including the releasefilm, and an electronic device including a display panel manufactured byusing the release film.

BACKGROUND ART

In a display panel, a photolithography method or a screen printingmethod has been used in order to form a bezel pattern in the relatedart, but a process for forming a pattern is complicated, themanufacturing cost thereof is expensive, or there is a problem in theperformance.

Thus, there is a need for developing a method which is simpler than themethod for forming a bezel pattern in the related art and may improvethe performance thereof while reducing the costs thereof.

DISCLOSURE Technical Problem

The present application has been made in an effort to provide a methodfor forming a bezel pattern of a display panel, which may reduce thecosts thereof or may improve the performance of the display panel byimproving process efficiency or simplifying the process.

Technical Solution

An exemplary embodiment of the present application provides a method forforming a bezel pattern of a display panel, the method including:attaching a release film including a non-pattern portion and havingadhesion to a panel; printing at least one bezel pattern by applying anink composition on the panel; and removing the release film from thepanel.

Another exemplary embodiment of the present application provides arelease film used in the method for forming a bezel pattern of a displaypanel.

Still another exemplary embodiment of the present application provides arelease film for forming a bezel pattern of a display panel including anon-pattern portion.

Yet another exemplary embodiment of the present application provides adisplay panel including the release film.

Still yet another exemplary embodiment of the present applicationprovides an electronic device including a display panel manufactured byusing the release film.

Advantageous Effects

The method for forming a bezel pattern of a display panel according toan exemplary embodiment of the present application may improve theprocess efficiency or may improve the performance of the display panel.

DESCRIPTION OF DRAWINGS

FIG. 1 illustrates a release film including a pattern portion and anon-pattern portion, which are separable from each other according to anexemplary embodiment of the present application.

FIG. 2 illustrates a panel from which a release film of a patternportion is removed after the release film is attached to the panelaccording to an exemplary embodiment of the present application.

FIG. 3 illustrates a panel for printing a plurality of bezel patterns onone panel according to an exemplary embodiment of the presentapplication.

FIG. 4 illustrates a bezel pattern which is a printed material fromwhich a release film is removed after printing according to an exemplaryembodiment of the present application.

FIG. 5 illustrates a bezel pattern printed according to Example 1.

FIG. 6 illustrates a bezel pattern printed according to Example 2.

FIG. 7 illustrates a bezel pattern printed according to Example 3.

MODE FOR INVENTION

The advantages and features of the present application, and methods ofaccomplishing the advantages and features will become obvious withreference to exemplary embodiments to be described below in detail alongwith the accompanying drawings. However, the present application is notlimited to the exemplary embodiments to be disclosed below, but will beimplemented in various forms different from each other. The exemplaryembodiments are merely intended to make the disclosure of the presentapplication complete and to completely notify the person with ordinaryskill to which the present application pertains of the scope of theinvention, and the present application is only defined by the scope ofclaims. The size and relative size of the constituent elements marked inthe drawings may be exaggerated for clarity of description.

Unless otherwise defined, all terms including technical and scientificterms used in the present specification may be used as the meaning whichmay be commonly understood by the person with ordinary skill in the artto which the present application pertains. Terms defined in commonlyused dictionaries should not be interpreted in an idealized or excessivesense unless clearly and particularly defined.

Hereinafter, the present application will be described in detail.

A “bezel” used in the present specification means at least one borderportion included in a display panel. The bezel may be included in aregion other than an effective screen portion. Further, a sensorportion, a camera portion, a logo portion, a button portion, or an openportion may be included in the border portion region.

A “bezel pattern” used in the present specification means a patternformed in the bezel portion. The bezel pattern may be included in otherregions such as the sensor portion, the camera portion, the logoportion, the button portion, or the open portion. The bezel pattern mayalso be a design pattern or a black matrix pattern.

An exemplary embodiment of the present application provides a method forforming a bezel pattern of a display panel, the method including:attaching a release film including a non-pattern portion and havingadhesion to a panel; printing at least one bezel pattern by applying anink composition on the panel; and removing the release film from thepanel.

In an exemplary embodiment of the present application, the release filmfurther includes a pattern portion, and the pattern portion may beseparable from a non-pattern portion.

FIG. 1 illustrates a release film 10 in which a pattern portion 20 and anon-pattern portion 30 are cut according to an exemplary embodiment ofthe present application.

In an exemplary embodiment of the present application, the method mayfurther include removing the release film of the pattern portion fromthe panel after attaching a release film including a pattern portionwhich is separable from a non-pattern portion to the panel.

In an exemplary embodiment of the present application, it is preferredthat in a release film, adhesion of the non-pattern portion is equal toor greater than that of the pattern portion.

An adhesion of the non-pattern portion may be equal to that of thepattern portion as long as the non-pattern portion and the patternportion are separable from each other. As an example, the adhesion ofthe non-pattern portion may be equal to that of the pattern portion aslong as a boundary line between the non-pattern portion and the patternportion is formed in the form of a stitch and thus the non-patternportion and the pattern portion are easily separable. As anotherexample, the adhesion of the non-pattern portion may be equal to that ofthe pattern portion as long as the thickness of the boundary linebetween the non-pattern portion and the pattern portion is 1% to 90% ofthe thickness of a region other than the boundary line and thus thenon-pattern portion and the pattern portion are easily separable fromboundary line.

In addition, since a release film of the pattern portion in thenon-pattern portion and the pattern portion is first removed, a patternis printed on a panel, and then a release film of the non-patternportion is removed, the adhesion of the portion which is removed latermay be greater than that of the portion which is removed first.

In an exemplary embodiment of the present application, in removing therelease film of the pattern portion from the panel, the pattern portionmay be mechanically removed by making the adhesion of the patternportion weaker than that of the non-pattern portion, or may be removedby being immersed in a specific solvent. Alternatively, it is possibleto use a method of applying heat to, irradiating laser on, orirradiating UV on the pattern portion.

FIG. 2 illustrates that a release film of a pattern portion is removedafter attaching the release film 10 to a panel 40 according to anexemplary embodiment of the present application.

In an exemplary embodiment of the present application, the release filmmay have a thickness of 100 μm or less, specifically from 1 μm to 50 μm,and more specifically from 1 μm to 30 μm. In order to enhance thesharpness of the pattern edge, it is preferred that the thickness is 100μm or less. When the thickness is 1 μm or more, solvent resistance to aprinting composition is excellent during printing.

In an exemplary embodiment of the present application, the release filmmay include a substrate film, and an adhesive layer.

According to an exemplary embodiment of the present application, thesubstrate film may be a plastic film. Specifically, the substrate filmmay be a polyester-based film, a polyolefin-based film, apolyimide-based film, a nylon-based film, or a mixed resin film thereof,and more specifically may be a film selected from the group consistingof polyethyleneterephthalate (PET), polybutyleneterephthalate (PBT),polyethylenenaphthalate (PEN), polybutylenenaphthalate (PBN),polyethylene (PE), polypropylene (PP), polyimide (PI), nylon, and amixed resin thereof.

In an exemplary embodiment of the present application, the adhesivelayer needs to have solvent resistance, chemical resistance, and oilresistance in order for a composition for printing not to penetrate intothe inner side of a protective film during printing. For example, it ispossible to use an acrylic, silicone-based, or urethane-based adhesiveas the adhesive layer.

In an exemplary embodiment of the present application, the non-patternportion may be a portion including one or two or more selected from thegroup consisting of an effective screen portion, a sensor portion, acamera portion, a logo portion, a button portion, and an open portion.

In an exemplary embodiment of the present application, the method forforming a bezel pattern may be a method for printing one bezel patternon one panel, or a method for printing two or more bezel patterns on onepanel.

In an exemplary embodiment of the present application, when one bezelpattern is printed on one panel, a release film may be attached to apanel which is cut in advance. In this case, an additional process ofalignment may be needed in attaching the release film.

In an exemplary embodiment of the present application, when one bezelpattern is printed on one panel, a panel which is not cut in advance mayalso be used in attaching the release film on the panel. In this case,the method may further include cutting a panel according to the form ofthe bezel pattern after printing the bezel pattern.

According to an exemplary embodiment of the present application, inorder to print two or more bezel patterns on one panel, the method mayfurther include cutting a panel according to the form of the bezelpattern after printing the bezel pattern.

The method for forming a bezel pattern according to an exemplaryembodiment of the present application may include removing the releasefilm from the panel after cutting the panel according to the form of thebezel pattern after printing the bezel pattern.

The method for forming a bezel pattern according to an exemplaryembodiment of the present application may include cutting the panelaccording to the form of the bezel pattern after removing the releasefilm from the panel after printing the bezel pattern.

FIG. 3 illustrates a panel for printing a plurality of bezel patterns onone panel. When each panel is cut according to the form of the bezelpattern after the bezel pattern is printed as in FIG. 3, there is anadvantage in that an additional process of alignment is not needed.

In printing the bezel pattern according to an exemplary embodiment ofthe present application, an ink composition may be applied on an entiresurface or a part of the panel.

In printing a bezel pattern according to an exemplary embodiment of thepresent application, the printed pattern may have a line height (height)from 0.5 μm to 10 μm, specifically from 0.5 μm to 5 μm. When a bezelpattern is printed using a screen printing method in the related art,the line height of the bezel pattern is 20 μm or more, and therefore,the level difference is high. Therefore, since cracks are frequentlygenerated by the high level difference, there is a disadvantage in thatthe performance of a display may deteriorate. However, when the methodof the present application is used, it is possible to implement a lineheight from 0.5 μm to 10 μm, and therefore, there is an advantage inthat the performance of a display may be improved because cracks arescarcely generated.

A printing method is not particularly limited in printing a bezelpattern according to an exemplary embodiment of the present application.Specifically, it is possible to use a method selected from the groupconsisting of spin coating, reverse offset, ink jet printing, gravurecoating, micro gravure coating, kiss gravure coating, comma knifecoating, roll coating, spray coating, Meyer bar coating, and slit diecoating.

In the panel according to an exemplary embodiment of the presentapplication, removing the release film may remove a release film of anon-pattern portion. Specifically, a remaining release film afterprinting may be mechanically removed, removed by being attached to anadhesive tape, or removed by being immersed in a specific solution.Alternatively, it is possible to use a method of applying heat to,irradiating laser on, or irradiating UV on the remaining release filmafter printing.

FIG. 4 illustrates a bezel pattern which is a printed material fromwhich a release film is removed after printing according to an exemplaryembodiment of the present application.

An exemplary embodiment of the present application provides a releasefilm used in the method for forming a bezel pattern of a display panel.

An exemplary embodiment of the present application provides a releasefilm for forming a bezel pattern of a display panel including anon-pattern portion. The release film further includes a patternportion, and the pattern portion may be separable from a non-patternportion. The description on the release film is as described above.

An exemplary embodiment of the present application provides a displaypanel including the release film.

Examples of the display panel include a plasma display panel (PDP), aliquid crystal display (LCD) panel, an electrophoretic display panel, acathode-ray tube (CRT) panel, an OLED display panel, or various touchpanels.

An exemplary embodiment of the present application provides anelectronic device including a display panel manufactured by using therelease film.

Hereinafter, the present application will be described in more detailthrough Examples and Comparative Example. However, the followingExamples and Comparative Example are provided for illustrative purposesonly, and the scope of the present application is not limited thereby.

Example 1

A release film having a thickness of 20 μm, which had been cut inadvance, was attached to a pattern surface of glass, and then therelease film of a pattern portion was removed. At this time, a method ofremoving the release film of the pattern portion by attaching to anadhesive tape was used. An entire surface of a printed material to whichthe release film was attached was coated using a spin coater. At thistime, the line height of the pattern was measured as 1 μm. Thereafter,the release film of a non-pattern portion was removed. At this time, amethod of removing the release film of the non-pattern portion byattaching to an adhesive tape was used. FIG. 5 illustrates a bezelpattern printed according to Example 1.

Example 2

A release film having a thickness of 20 μm, which had been cut inadvance, was attached to a pattern surface of glass, and then therelease pattern of a pattern portion was removed. At this time, a methodof removing the release film of the pattern portion by attaching to anadhesive tape was used. A printing material was coated on an entiresurface of a silicone blanket using a Mayer bar. The blanket with theentire surface coated with the printing material was brought intocontact with a pattern surface of glass to which the release film wasattached, and then transferred thereon. At this time, the line height ofthe pattern was measured as 1 μm. Thereafter, the release film of thenon-pattern portion was removed. At this time, a method of removing therelease film of the non-pattern portion by attaching to an adhesive tapewas used. FIG. 6 illustrates a bezel pattern printed according toExample 2.

Example 3

A release film having a thickness of 20 μm, which had been cut inadvance, was attached to a pattern surface of glass, and then therelease film of a pattern portion was removed. At this time, a method ofremoving the release film of the pattern portion by attaching to anadhesive tape was used. A printing material was coated on an entiresurface of a silicone blanket using an off set apparatus, and then theblanket coated with the printing material was brought into contact witha pattern surface of glass to which the release film was attached, andthen transferred thereon. At this time, the line height of the patternwas measured as 0.5 μm. Thereafter, the release film of the non-patternportion was removed. At this time, a method of removing the release filmof the non-pattern portion by attaching to an adhesive tape was used.FIG. 7 illustrates a bezel pattern printed according to Example 3. Itcould be confirmed that a clearer bezel pattern was formed compared toExample 1 using a spin coating method or Example 2 using a Mayer barcoating method.

Comparative Example 1

A bezel pattern was formed on glass through a screen printing method. Atthis time, the line height of the pattern was measured as 15 μm.

When the line height of the pattern is high, a short circuit occurs andcracks are generated due to the level difference, thereby leading todeterioration of durability. Furthermore, an optical adhesive may alsobe used in order to alleviate the level difference, but at this time,there is a problem in that a product appears dull because the productbecomes thick.

Further, bubbles may be generated by a level difference occurring due toa pattern line height during a lamination work of a panel and variousfilms. When bubbles are generated, a high temperature and high pressureprocess may be required in order to remove bubbles, and bubbles may notbe removed even at high temperature and high pressure, which isproblematic.

It is understood by a person with ordinary skill in the art to which thepresent application pertains that various applications and modificationsmay be made within the scope of the present application based on thecontents.

Although the specific part of the present application has been describedin detail, it is obvious to those skilled in the art that such aspecific description is just a preferred embodiment and the scope of thepresent application is not limited thereto. Thus, the substantial scopeof the present application will be defined by the appended claims andequivalents thereto.

DESCRIPTION OF REFERENCE NUMERALS

-   10: Release film-   20: Pattern portion-   30: Non-pattern portion-   40: Display panel

The invention claimed is:
 1. A method for forming a bezel pattern of adisplay panel, comprising: attaching a release film comprising anon-pattern portion and having adhesion to a panel; printing at leastone bezel pattern by applying an ink composition on the panel; andremoving the release film from the panel, wherein the release filmfurther comprises a pattern portion, and the pattern portion isseparable from the non-pattern portion, and wherein in the release film,adhesion of the non-pattern portion is equal to or greater than that ofthe pattern portion.
 2. The method of claim 1, further comprising:cutting the panel according to the form of the bezel pattern afterprinting the bezel pattern.
 3. The method of claim 1, furthercomprising: removing the release film of the pattern portion from thepanel after attaching the release film to the panel.
 4. The method ofclaim 3, wherein the release film of the pattern portion is removed byusing a method of applying heat, irradiating laser, or irradiating UVthereto.
 5. The method of claim 1, wherein the release film has athickness of 100 μm or less.
 6. The method of claim 1, wherein therelease film has a substrate film; and an adhesive layer.
 7. The methodof claim 6, wherein the substrate film is selected from the groupconsisting of polyethyleneterephthalate (PET), polybutyleneterephthalate(PBT), polyethylenenaphthalate (PEN), polybutylenenaphthalate (PBN),polyethylene (PE), polypropylene (PP), polyimide (PI), nylon, and amixed resin thereof.
 8. The method of claim 1, wherein the non-patternportion comprises one or two or more selected from the group consistingof an effective screen portion, a sensor portion, a camera portion, alogo portion, a button portion, and an open portion.
 9. The method ofclaim 1, wherein the printed pattern has a line height from 0.5 μm to 10μm in printing the bezel pattern.
 10. The method of claim 1, wherein aprinting method in printing the bezel pattern is reverse offset.
 11. Themethod of claim 1, wherein a printing method in printing the bezelpattern is selected from the group consisting of spin coating, ink jetprinting, screen printing, gravure coating, micro gravure coating, kissgravure coating, comma knife coating, roll coating, spray coating, Meyerbar coating, and slit die coating.